A fulfillment of diminished expectations.
BY TONY SWAN, September 2006

Disappointment is invariably related to expectations. The higher they are, the greater the likelihood the object of those expectations won’t quite measure up. Do you hear Shelby GT500 convertible disappointment impending? You do. But let us hasten to add that these aren’t major disappointments. In fact, for the most part, we simply want to, shall we say, square GT500 expectations with reality.

Based on our July comparison test, pitting a Shelby GT500 coupe against a Corvette, we’d already relaxed our performance expectations for the convertible, even before it rolled into our parking lot. For example, since our GT500 test coupe wasn’t any quicker than the old SVT Mustang Cobra, there was no reason to believe the convertible, weighing in 112 pounds heavier at 4008, would do any better. And it did not, thus fulfilling our slightly diminished expectations, although we found that in this area our expectations hadn’t been diminished quite enough. At 4.8 seconds to 60 mph, the convertible was 0.3 second slower than the coupe, which ain’t really slow, but the disparity was progressive. The convertible was 0.8 second slower to 100 mph — 11.1 versus 10.3 — and also slower through the quarter-mile: 13.4 seconds at 108 mph versus 12.9 at 112. This is more than we expected for a 112-pound difference, and we think our test car’s supercharged 5.4-liter V-8 was a tad soft, a suspicion enhanced by a nasty ticking noise coming from the engine. Exhaust leak? Or…?

In addition to softer acceleration, we were also prepared for higher ambient noise levels — a normal consequence of traditional softtops. But in this scoring category we were pleasantly surprised. There’s wind noise, yes, but this is a high-quality top that does a better-than-average job of damping buffeting and roar. The biggest source of interior racket came from the Goodyear Eagle F1 Supercar tires and the suspension — all of it related to what was going on underfoot. On pavement cross-hatched with expansion joints and/or patching, every seam was tangible to the occupants, as both noise and thumping. The suspension bushings seem to be made of granite.

Similarly, the tires are pavement sensitive, quiet on smooth asphalt, singing at unpleasant frequencies on various concrete compounds. But for all that, the convertible’s decibel readings were quieter than the coupe’s at idle, quieter at wide-open throttle, and identical at a 70-mph cruise.

We have mixed reactions here to the absence of the Shelby stripes on this convertible — they’re a dealer option. We judged the stripes as a “low” in our July test, but we are not unanimous on that score, and it’s fair to say the Shelby doesn’t really have much curbside charisma without them. Along these lines, we also think the SVT people could have taken more pains with this car’s interior. Aside from a couple of badges, there’s not much that sets the Shelby apart from its Mustang GT counterparts, and it’s pretty plain considering the car’s price. And speaking of price, we’re already hearing tales of dealers asking $15,000 to $20,000 over the MSRP. Ford has no real control over this, and the sad part is these gougers will probably get their markups.

In all the foregoing, we don’t perceive really serious disappointments. But there is one element that’s impossible to rationalize: a rubbery chassis. It doesn’t take much of a bump to provoke shudders in this GT500’s structure, regrettable in an ordinary convertible, unacceptable in one with performance aspirations. This trait was a big surprise, since we gave the Mustang GT convertible high marks for chassis rigidity. Could the extra power, higher (by 335 pounds) curb weight, and heftier forward weight bias account for this? Could be.

However, we suspect that none of our reservations is going to matter to prospective owners. And in fact, there’s much to rejoice in here. The six-speed gearbox is a wonderful device to manipulate, the steering is quick and communicative, braking performance is strong, the seats are supportive and long-haul comfortable, and supercharger whine adds an enjoyable audible element to full-throttle acceleration.

Beyond that, there’s no question that these cars will be instant collectibles. That alone makes this Shelby another winner, whatever expectations we may entertain.